1. Field of the Invention
The present invention relates to video coding and decoding, and more particularly, to an apparatus and method for predicting a motion vector when video coding or decoding is performed.
2. Description of the Related Art
According to an H.264 video compression standard for encoding and decoding moving picture data, various sized blocks are used to calculate a motion vector. Also, motion vector information of adjacent blocks is used to calculate a motion vector of a block.
Among the various sized blocks, there is a 16×16 macro block divided into 16 4×4 blocks. Here, to obtain motion vectors of the 4×4 blocks, a 16-operation sequential calculation process is necessary. Accordingly, it takes a great amount of time to calculate the motion vectors. However, as disclosed below, since a motion vector of a certain block can be simultaneously calculated with a motion vector of another block, if a motion vector of a block adjacent to a desired block is known already, the conventionally required 16 operations for calculating a motion vector can be reduced.